Racers please chime in--Thanks

I use Brad Penn oil 20w 50 and change my oil every 30 to 35 passes. Cut the filter each time! As for the trans, I use aluminum parts and change that oil & filter [band adjustment] every fifty passes. [904 trans/deep pan] I also use one quart of SAE non detergent 30 weight oil when installing the trans fresh. I will also add one quart of "30" weight on the second trans service of the year. Otherwise I use the type "F" fluid most of the time, but have used the ATF + 4 with no problems using either. [never a shifting issue]